Fiber collimator with fresnel lens

Abstract

The present disclosure provides an optical fiber collimator structure employing a Fresnel lens. An example optical fiber collimator includes an optical fiber to transmit optical signals, the optical fiber being aligned with a central axis of the optical fiber collimator. A capillary supports the optical fiber. A support element receives the optical fiber as it enters the optical fiber collimator. A Fresnel lens is aligned with the optical fiber and configured to receive the optical signals from the optical fiber.

1 . An optical fiber collimator comprising:
 an optical fiber to transmit optical signals;   a capillary to support the optical fiber; and   a Fresnel lens aligned with the optical fiber and to receive the optical signals.   
     
     
         2 . The optical fiber collimator of  claim 1 , wherein a first end of the Fresnel lens is arranged to receive the optical signals from an output facet of the optical fiber, the first end being defined by an angle relative to a central axis of the Fresnel lens. 
     
     
         3 . The optical fiber collimator of  claim 2 , wherein the first end is substantially planar. 
     
     
         4 . The optical fiber collimator of  claim 2 , wherein one or more of the optical fiber and capillary are aligned with the central axis. 
     
     
         5 . The optical fiber collimator of  claim 2 , wherein the Fresnel lens further comprises a second end opposite the first end, the second end being defined by a plurality of concentric circles. 
     
     
         6 . The optical fiber collimator of  claim 5 , wherein each of the plurality of concentric circles have a common width. 
     
     
         7 . The optical fiber collimator of  claim 5 , wherein a first concentric circle of the plurality of concentric circles has a first width different from a second width of a second concentric circle of the plurality of concentric circles. 
     
     
         8 . The optical fiber collimator of  claim 1 , wherein the Fresnel lens has a first depth at a first side and a second depth at a second side. 
     
     
         9 . The optical fiber collimator of  claim 1 , further comprising an antireflective coating on one or more surfaces of the Fresnel lens. 
     
     
         10 . The optical fiber collimator of  claim 9 , wherein an output facet of the optical fiber comprises an antireflective coating, the output configured to transmit the optical signal to the Fresnel lens. 
     
     
         11 . An optical fiber collimator comprising:
 an optical fiber to transmit optical signals, the optical fiber aligned with a central axis of the optical fiber collimator;   a capillary to support the optical fiber;   a support element to receive the optical fiber as it enters the optical fiber collimator; and   a Fresnel lens aligned with the optical fiber and to receive the optical signals.   
     
     
         12 . The optical fiber collimator of  claim 1 , wherein the optical fiber collimator is coupled to one or more optical elements. 
     
     
         13 . The optical fiber collimator of  claim 12 , wherein the optical element is one or more of a photodetector, an optical lens, a mirror, a filter, a Bragg grating, a second collimator, or a second optical fiber. 
     
     
         14 . The optical fiber collimator of  claim 11 , further comprising an antireflective coating on one or more surfaces of the Fresnel lens. 
     
     
         15 . The optical fiber collimator of  claim 14 , wherein a first surface of the Fresnel lens has a first antireflective coating and a second surface of the Fresnel lens has a second antireflective coating. 
     
     
         16 . The optical fiber collimator of  claim 15 , wherein the first surface of the Fresnel lens is defined by an angle relative to the central axis. 
     
     
         17 . The optical fiber collimator of  claim 16 , wherein a surface of the capillary is defined by the angle, the surface of the capillary configured to mate with the first surface of the Fresnel lens. 
     
     
         18 . The optical fiber collimator of  claim 11 , wherein the optical fiber collimator is substantially cylindrical. 
     
     
         19 . The optical fiber collimator of  claim 11 , further comprising a sleeve around an outer surface of the capillary. 
     
     
         20 . The optical fiber collimator of  claim 19 , wherein a position or orientation of the Fresnel lens is fixed relative to one or more of the optical fiber, the capillary, the sleeve, or the support element.